1.	(a)	(i)
	2
(ii)	No rotation / restricted rotation around double bond(1)	1
 
(b)	(i)	

	1
 
(ii)	One end of C=C bond has 2 identical atoms / groups attached (1)
Or if cyclobutane –
no movement / no C=C (1)	1
[5]

2.	(a)	(i)	e.g.
CH3CHBrCH2CH3 + KOH ® CH2=CHCH2CH3 + KBr + H2O
Or
CH3CHBrCH2CH3 + KOH ® CH3CH=CHCH3 + KBr + H2O
(1)
allow ionic equation with OH– and Br–	1
 
(ii)	Elimination (1)	1
 
(b)	(i)	brown / red-brown / orange / red-orange / yellow to colourless
/ fades / decolourises / gets paler (1)	1
 
(ii)	
	2,3-dibromobutane (1) accept 3-bromobutan-2-ol if correct
structure drawn for hydroxy product	2
 
(c)	 (1 mark for each)
	allow:	2

(ii)	Restricted (or ‘no’) rotation about double bond /
2 different groups at each end of double bond (1)
geometrical / cis-trans (1)	2
[9]

3.	(a)	Group of compounds with the same general
formula (1) that
differ by –CH2- (1)
Same or similar chemical properties / same	3
functional group (1)
 
(b)	(i)	
	At least one repeat unit (1)
evidence of extension of chain (1)	2
consequential on correct repeat unit
 
(ii)	CH2 (1)
empirical formula of propene/ the repeat unit (1)
since polymer made by addition reaction / no loss of 
small molecules (1)	3
 
(c)	Different chain lengths / areas of crystalline and amorphous structure (1)	1
 
(d)	(i)	C-F bond strong / high bond enthalpy / bond not	1
easily broken / steric hindrance by fluorine around carbon (1)
 
(ii)	Non–stick coatings e.g. in saucepans, in pipes, on skis,
stain–proofing of fabrics, waterproof clothing. (1)	1

(e)	Only single / sigma bonds in ethane (1)
	Ethene also has p bond (1)
p bond weaker (and breaks) / electrons in p bond	3
more accessible (1)
[14]

4.	(a)	It is a mixture / not a single compound	1
(b)	(i)	2,4-dimethylpentane	1
(ii)	C7H16	1
(iii)	More volatile / lower boiling point / vaporises more readily / branched so
doesn’t knock / higher octane number	1
(iv)	Heat / high temperature / ³ 200 °C (1)
Silica / alumina (catalyst) /zeolites (1)	2
(v)	Diagram should show:
	Test tube containing paraffin absorbed on suitable absorbent – (1)
absorbent can be just shown in the diagram
	Aluminium oxide catalyst (1)
Heat catalyst (1)
Recognition of collection of gas over water /gas syringe (1)	4
	Penalties
–1 for poor diagram
 
(c)	(i)	(CH3)2C = CH2
ACCEPT (CH3)2CCH2	1
(ii)	Elimination	1
(iii)	Potassium hydroxide / KOH / NAQH (1)
Ethanolic / alcoholic solution + heat / reflux (1)	2
[14]

5.	(a)	(i)	C2H6 + Br2  ® C2H5Br + HBr (1)
	C2H4 + Br2  ® CH2BrCH2Br ALLOW C2H4Br2 (1)	2
IGNORE STATE SYMBOLS
 
(ii)	(Free) radical / homolytic (1) substitution (1)
Electrophilic (1) addition (1)	4
 
(b)	(i)		1
 
(ii)	
	1
 
(iii)	Persists in the environment / persisting as litter
	OR non-biodegradable / not broken down by bacteria (1)
	because of strong C-Cl bond (1)
	OR
	combustion / burning (1)
	produces toxic gases /acidic gases/HCI (1)
	NOT chlorine	2
[10]

6.	(a)	(i)	a particle / species /group with an unpaired electron /OWTTE	1
(ii)		1
(iii)	homolytic	1
 
(b)	B and C	1
(c)	(i)	C12    +    CH4    ®    CH3Cl    +    HCl	1
(ii)	+242  +  4  +  –339  =  –93 kJ mol–1
(A     +  B +      F)
OR
+4 – 97 = –93 kJ mol–1
(B + C)
Method (1)
answer with units (1)	2

(d)	(i)	-242 kJ mol–1	1
(ii)	Exothermic because a bond has been formed.	1
(e)	Less endothermic (1)
the bond is weaker (1)	2
[11]

7.	(a)	(i)	CH4 + C12 ® CH3Cl + HCl (1)	1
(ii)	UV (radiation) / Sunlight (1)   Not light	1
 
(b)	(i)	
	2
(ii)	restricted rotation around double bond (1)
Allow no rotation at room temperature
two different groups on each double bonded carbon (1)	2
(iii)	2,3-dichlorobutane (1)	1
[7]

8.	(a)	(i)	C2H6(g)/(I) ® C2H4(g) + H2(g)
If a state symbol is missing (0)
If (aq) (0)	1
(ii)	At high pressure reaction goes in direction to reduce
pressure/to oppose change by Le Chatelier’s principle (1)
towards side with fewer molecules/moles (1)	2
 
(b)	Shapes of orbitals between and above carbon

If p orbitals drawn msut show overlapping
	Shapes (1) ACCEPT crescents for p bonds NOT lines for s bond	2
Labels (1)

(c)	Addition of bromine water/solution (1)
from yellow/brown/orange to colourless (1)
OR
acidified potassium manganate(VII) (1)
from pink/purple to colourless (1)	2
 
(d)	Addition (1)
Elecrophilic/electrophile OR appropriate explanation (1)	2
[9]

9.	(a)	σ bond:
diagram showing the head on overlap between two (s or p or s & p) orbitals (1),

	π bond:
diagram showing the side by side overlap of two (p) orbitals (1)

		2

(b)	(i)	Methane is tetrahedral (1) – stated or drawn 3D
It has 4 pairs of electrons (1)
Which repel to a position of maximum separation / minimum repulsion
could be awarded from (ii) (1) – can score even if first two are wrong
Do not allow atoms or bonds repelling	3
(ii)	Shape of CO2 is linear (1) – can be a diagram
1st mark is stand alone 
	because there are 2 pairs of σ electrons / 2 sets of bonding electrons / 2
areas of negative charge/2 double bonds (1)	2
[7]

10.	(a)	H2 / hydrogen NOT H (1)
Ni / nickel
OR platinum / Pt / palladium / Pd (1)
(Ni) 140 – 180 ° C / heat (1)	3
OR (Pt / Pd) room temperature
If no reagent but other parts correct (1)
Incorrect reagent (0)
 
(b)	(i)	
	1
(ii)	electrophile / electrophilic IGNORE any reference to addition	1
 
(c)	potassium manganate(VII) / potassium permanganate / MnO4– / 
manganate(VII) ions IGNORE acid or alkali	1
ACCEPT name or formula

(d)	

Correct structure (1) – only one repeat until identified
Continuation (1)
IGNORE (   )n	2
[8]

11.	(a)	(i)	(Free) radical
ACCEPT homolytic radical
NOT radical ion	1
 
(ii)	CH3CH3 + Br2 ® CH3CH2Br + HBr
OR
C2H6 + Br2 ® C2H5Br + HBr
	ACCEPT multiple substitution only if the equation balances
Can be full structural formula
If H2 is one product then  (0)	1
 
(b)	(i)	CH2 = CH2+Br2 → BrCH2CH2Br / CH2BrCH2Br /	CH2–CH2
			|     |
			Br    Br
	Ethene shown with double bond + Br2  (1)
product  (1)	2
 
(ii)	1,2 (–) dibromoethane only – mark independently of (i)
IGNORE punctuation	1
 
QWC	(c)	Ethene has a π / double bond  (1)
Ethane has σ only / single only / no π / no double bond (1)
	π (in ethene) weaker than C–H (in ethane) / high electron
density in C=C relative to C–H bond  (1)	3
[8]

12.	(a)	(i)	

	Can show C in straight line if H’s clearly cis or trans.
If H is missing once but bond is shown, no penalty.
If all H’s missing then (1) only awarded for both structures
ALLOW 	2
 
(ii)	(Both have) no/restricted  rotation about C=C (rotation would
require π bond to break)  (1)
	but but-1-ene has two identical groups on a doubly
bonded carbon atom  (1)
but-2-ene does not  (1)
OR other way round	3
 
(iii)

Do not need to show all bonds eg can be –CH3, –C2H5	1

(b)	(i)	

	Skeleton  (1)
Indication of continuation conditional on a two carbon
saturated chain in the skeleton.  (1)	2
 
(ii)	Unreactive OR  non-biodegradable  (1)
	So occupies / fills site OR remains in the site OR  causes visual pollution (1)
2nd mark consequential on 1st
NOT “Do not decompose/decay” for 1st mark but allow 2nd mark	2
[10]

13.	(a)	Alkene	1
 
(b)	CH2=CHCH2CH3 / CH3CH=CHCH3 / CH2 = C(CH3)2 / CH2=C(CH3)CH3
double bond need not be shown
ACCEPT displayed formula
Mark independently of a
Watch for incorrect numbers of H in the middle of the chain	1
[2]

14.	(i)
	1

(ii)

ALLOW all dots or crosses
ALLOW TE for a butene/pentene in (a)(i) 
IGNORE circle	1
[2]

15.	(CH3)2C=CH2
ALLOW displayed formula (1)
ALLOW C(CH3)2=CH2
CH3C(CH3)=CH2
CH3CCH3=CH2
CCH3CH3=CH2
CH3CH3C=CH2
	double bond need not be shown, but if single bond displayed (0)

	Mark independently
No transferred error allowed	2
[2]

16.	(a)	(i)	2(-)chloropropane
 No internal TE from name to structure
MUST be fully displayed	2

(ii)	

	Mark independently
Must attack the carbon
ALLOW attack by oxygen or negative charge or lone pair	2

NOT C+
 
(b)	(i)	Elimination
NOT in conjunction with additional incorrect information
eg “nucleophile”	1
 
(ii)	Sodium hydroxide / NaOH/potassium hydroxide / KOH (1)
Any additional incorrect reagent (0)
NOT alkali on its own for 1st mark
	Alcoholic solution / ethanolic solution and heat / warm / reflux (1)
2nd mark is dependent on mention of correct reagent or “alkali”
“aqueous” negates 2nd mark eg KOH(aq) + heat (1) – ie reagent mark
NaOH(alc) + heat (2)	2
 
(c)	(i)	Hydrogen/H bonding	1
 
(ii)	

	H-bond and rest of molecule (1)
angle must be between 3 atoms for a correct H bond (1)
ALLOW HOH 106-108°	2

(d)	(i)	
 IGNORE any “n” in this diagram
	Brackets optional but continuation must be shown
4 carbon chain with 6Cs overall in structure (1)
methyl groups can be on C1 and C3, C1 and C4, C2 and C4, C2 and C3 (1)
	      1 max	2
 
(ii)	(big molecule) so large number of electrons (1)
	Hence large/strong van der Waals’ forces
(to be overcome to change state)(1)	2
[14]

17.	(a)	(i)	
	IGNORE punctuation
ALLOW 1 max if correct answer is pre-fixed by cis / trans	2
 
(ii)	From orange/yellow/brown	to	colourless (1)
NOT red		NOT clear	1
 
(iii)	addition (1)
electrophilic (1)
in either order	2
 
(iv)	

Methyl group need not be displayed	1

(b)	(i)	Van der Waals’ (forces)
ACCEPT Van der Walls
NOT vdw	1
 
(ii)	Q because (unbranched) so greater area of contact / closer packing
(between molecules) (1)
	hence greater Van der Waals/vdw forces (1)
2nd mark dependent on 1st
Incorrect isomer chosen (0)
Fully correct reverse argument (2)	2
[9]

18.	(a)	(i)
	1
Accept CH3 in branches
But do not allow bond directly to H
i.e.

Reject 

(ii)
	1
Accept 
Reject bond pointing directly to H i.e.
in OH i.e.

Reject Hs missing from carbons i.e.

(b)	Isomer 1
 (1)
	Isomer 2
 (1)
Accept 90° bond angles e.g

OR

ACCEPT

	If incorrect alkene eg but-2-ene, allow (1) for both cis and trans isomers	2
[4]

19.	(a)	(i)	(C2H6 + Br2) → C2H5Br + HBr
OR
multiple substitution e.g.
C2H6 + 2Br2 → C2H4Br2 / CH3CHBr2/CH2BrCH2Br + 2HBr
C2H6 + 3Br2 → C3H3Br3 + 3HBr etc	1
Accept CH3C H2Br or full structural formula
Reject C2H6 + 3Br2 → 2C + 6HBr
 
(ii)	(C2H4 + Br2) → CH2BrCH2Br	1
Reject C2H4Br2
 
(b)	(i)	ethane C– H bond and ethene C=C bond (1)
ALLOW carbon–carbon if double in type of bond
ethane type: σ/sigma and ethene type: π/pi (1)
OR mark horizontally	2
Reject σ and π for ethene
 
(ii)	π/pi bond is weaker (than the σ/sigma bond)	1
Accept π/pi bond requires less energy to break
OR
π/pi bond has lower bond enthalpy
Reject π breaks more easily
Reject π bond is weak
	OR
π/pi bond has higher electron density (than the σ/sigma bond)
Accept π/pi bond has more accessible electron density
[5]

20.	(a)	(i)	(18 × 1.35) = 24.3/ 24.30 (kJ) (1)	1
 
(ii)	kJ from 1 mole =  /  / 24.3 × 88 (1)
	∆H = – 2140 (3SF) (kJ mol–1) (1)
Second mark must have negative sign and 3SF
Allow TE from incorrect value in (i)	2
Accept ∆H = – 2138.4/ –2138/+2138 (kJ mol–1)for 1 mark

(iii)	Incomplete combustion / combustion to C or CO. Not
complete combustion (1)	1
Reject not all of the propane burns.
Reject comments on accuracy of equipment.
 
(b)	(i)

+6490 = ∆Hc + (6 × 805 + 8 × 464)
∆Hc	=+6490 – 4830 – 3712
	= –2052 kJ mol–1
Accept –2050 (kJ mol–1)
	Balancing cycle with 5O2 and 10 O(g) (1)
∆H1 = (6 × 805 + 8 × 464) = (+) 8542 (kJ mol–1) (1)
Final value –2052 (kJ mol–1) (1)
IGNORE SF
Allow TE from an incorrectly calculated ∆H1 if method clear.	3
 
(ii)	H2O is gas in equation/ not standard state
OR mean bond energies differ from bond energies in these
compounds / Environment in these compounds changes bond
energies from the mean.	1
Accept H2O is liquid in ∆H combustion calculation but ges in bond energy calculation.
Reject “mean bond energies are used” without qualification
Reject all the substances are in the gasous state
 
(c)	(i)	Free radical (1) substitution (1)	2
Accept reverse order

(ii)	2C3H7• → C6H14 (1)
	Two (propyl) radicals may combine /a radical and a
molecule may produce C6H14 (in a propagation step) (1)	2
Accept C3H7• + C3H7• → C6H14 (1)
Accept multiples
Accept C3H7• + C3H8 → C6H14 + H• (1)
Full mechanisms may be shown
 
(d)	(i)	2-chloropropane: white precipitate/ solid /cloudiness (1)
Reject white colour
Reject creamy
	2-iodopropane: yellow precipitate / solid (1)	2
Accept ppt appears slowly with chloropropane and quickly with iodopropane (1)
Accept pale yellow precipitate
Accept white colour and yellow colour – 1 out of 2
 
(ii)	Ag+(aq) + I–(aq) → AgI (s)
	Formulae (1)
State symbols (1)
Minor error in formula with correct state symbols max 1	2
Accept max 1 out of 2 for wrong halide
 
(iii)	Propan-2-ol/ CH3CH(OH)CH3 (1)	1
Accept displayed formula

Reject molecular formula C3H7OH
[17]

21.	(a)	(i)	2,2,4-trimethylpentane
Ignore punctuation (Commas and hyphens may be interchanged)	1
Accept 2,4,4 - trimethylpentane
Reject pentan for pentane
2-dimethyl-4
methylpentane
2,2-dimethyl-4-methyl
pentane
2-methyl-4,4-dimethyl
pentane
2,4-trimethylpentane
 
(ii)	C4H9	1
Accept C8H18 → C4H9
 
(iii)	C2H4	1
Reject CH2CH2
 
(iv)	Positive because energy is required to break (C–C) bonds
(and not completely replaced (from new bonds made))
OR Positive because cracking requires (continuous) supply of
heat so must be endothermic	1
Accept two C–C bonds are broken and one C=C made
Reject positive because it only occurs at high temperature
 
(v)	C8H18 + 17/2 O2 → 8CO + 9H2O
	OR 2C8H18 + 17 O2 → 16CO + 18H2O
	OR C8H18 + 9/2 O2 → 8C + 9H2O (or doubled)
	Oxygen on left and correct formulae of products (1)
balancing (1)
Second mark depends on first and a sensible hydrocarbon
formula must be used.	2
Accept balanced equations including CO and/or C with CO2
17/2 can be written 8.5 or 8½
Allow balanced equations based on C8H18 with a smaller alkane in the products for 1 mark eg
C8H18 + O2 → CO + C7H16 +H2O (1)

(b)	(i)	Increase in pressure: No effect as number of
moles/molecules (of gas) doesn’t change during reaction (1)
	Increase in temperature: more NO as forward reaction
endothermic OWTTE (1)
	One mark for two correct predictions with incorrect explanations	2
Reject increase in temperature moves equilibrium to the right
 
(ii)	Rate increases as converter gets hotter (as reaction is
exothermic)	1
 
(iii)	N2 / nitrogen is (major) part of air/ N2 unreactive/ not
poisonous/ not a greenhouse gas / not acidic	1
Accept correct harmful properties of other 3 gases
 
(iv)	Line from level of reactants to maximum labelled EA (1)
	Curve of similar shape above existing curve, starting and
finishing at same levels, with maximum above original maximum (1)	2
[12]

22.	(a)	(i)
	1
Reject “Fl” for fluorine

(ii)	C–F bond is stronger/ they are stronger/the bonds are
stronger
	OR
C–F higher bond energy/ enthalpy
OR
they have a higher bond energy/enthalpy	1
Accept UV (photon) too low energy to break C–F bond
Reject C–F or C–Cl as an ionic bond
OR
C–Cl bond is weaker
OR
any reference to difference in polarity or difference in electronegativity
OR
references to hydrogen bonding/van der Waals forces
 
(iii)	neutral particles with an unpaired electron
OR
neutral species with an unpaired electron
OR
atoms/molecules with an unpaired electron (1)
Reject ions/elements/substances with…….
“unbonded electron/free electron/ lone electron/single electron” instead of “unpaired electron”
	uv radiation (1) stand alone
OR
uv light
OR
sunlight	2
Accept higher frequency than visible light
Reject homolytic fission
OR description of atoms taking electron from covalent bond OR just “high frequency light”

(b)	(i)

	brackets are not required
	If extension bonds are missing from both, give total 1
mark if all other atoms and bonds are correct	2
more than one repeat unit may be drawn but one repeat unit must then be clearly labelled or indicated by brackets, but only penalise this once
Reject –C=C–
OR
“Fl” for fluorine
[6]

23.	(a)	(i)	A and/or propene	1
Accept prop-1-ene
Reject A and any other letter
 
(ii)	B C and D (any order)
3 correct for 2 marks
2 correct for 1 mark
1 letter, correct or incorrect	O eg	B
2 letters both correct	1	BC
2 letters 1 correct 1 wrong	O	BE
3 letters, all correct	2	BCD
3 letters, 2 correct 1 wrong	1	BCE
3 letters, 1 correct 2 wrong	O	ABE
4 letters, 3 correct 1 wrong	1	BCDE
4 letters, 2 correct 2 wrong	O	ABDE
5 letters	O	ABCDE	2
 
(b)	(i)	2–bromopropane	2 (–) bromo (–) propane
2 Bromo Propane	2, bromopropane	1
Reject bromopropane
Reject bromo-2-propane
Reject 2-bromopropene

(ii)	poly(propene) or polypropene	1
Accept polly(propene)
Accept polypropylene
Reject poly porpene
Reject polypropane
 
(c)	(i)	potassium/sodium hydroxide (1)
	(concentrated)
ethanol(ic)/alcoholic AND heat/reflux	2
Accept KOH/NaOH
Reject alkali on its own
Reject any mention of water/aqueous/pressure (–1)
 
(ii)	Elimination (reaction)	1
Reject any qualification of elimination e.g nucleophilic /
electrophilic cracking
 
(d)	(i)	Cl2 ® 2Cl•
Ignore state symbols	1
Reject not 2 Cl(g)
Reject Cl2 →2Cl
 
(ii)	C3H8 + Cl2 ® C3H7Cl + HCl
Ignore state symbols	1
Reject 2Cl° + C3H8 → C3H7Cl + HCl
 
(iii)	2 (,) 3 (–)dimethyl butane (1) Ignore punctuation
Reaction between two
CH3¾CH¾CH3 (1) dot must be shown on central
carbon atom
Termination (1)	3
Accept C3H7° + C3H7° → C6H14
Accept chain termination
Reject 2,3 methylbutane
Reject CH3CHCH3°
[13]

24.	(i)	Ʃ∆Hf (products) – Ʃ∆Hf (reactants) / [(–394) + (2 × –242)] – (–75) (1)
	= –803 (kJ mol–1) (1)	2
correct answer without working scores (2)
–561 (kJ mol–1) scores (1)
any positive value scores zero
 
(ii)	(under standard conditions) water condenses / is a liquid (more heat evolved)	1
Accept reverse argument
Accept water is not in its standard state
Reject any answer in terms of average bond energies
Reject just “conditions are not standard”
 
(iii)	QWC
Any 4 of:
	H2 better because:
cheaper per kJ (1)
more energy per gram / less weight/mass to carry for same energy (1)
no CO2 /only H2O produced (at point of use) (1)
Reject just “cheaper”
Reject just “more energy”
Reject just “hard to store”
	H2 worse because: gas storage needs pressurised/large containers (1)
which are heavy (1)
needs to be cooled to very low temperature to be liquefied (1)
Accept converse argument
Reject hydrogen is flammable/ dangerous/explosive
	Ignore problems with refuelling	4
[7]

25.	(a)	(i)	(Concentrated) sulphuric acid/H2SO4 (1)
Water/H2O (1)
Any order	2
Accept phosphoric acid
1 HBr 2 NaOH/KOH (2)
H2SO4 + NaOH/KOH (1max)
H2O and high T and P and catalyst (1 max)
Reject dilute/aq sulphuric acid
H2SO4 + Na2Cr2O7 (0)
H2O alone (0)
H2O + × (eg H2O2) (0)
 
(ii)	Butan(e) -1,2-diol	1
Ignore punctuation
1,2-butan(e)diol
1,2-dihydroxybutane
Reject buta-1,2-diol
Reject but-1,2-diol
Reject 1,2-diolbutan(e)
Reject any formula
 
(iii)	1,2-dibromobutane	1
Ignore punctuation
Reject any formula
 
(iv)	Hydrogen bromide/HBr
Ignore (aq)	1
Accept KBr + H2SO4/H3PO4
Accept any other metal
Accept bromides
 
(b)	Two reactants come together to make one product	1
Accept one reagent added across double bond
Accept use judgement but in general look for ‘two…become one’
Accept ‘two or more reactants give one product’
Reject ‘adding 1 atom’
Reject just ‘unsaturated becomes saturated’
Reject just ‘the double bond breaks’
Reject ‘2 molecules are joined’
 
(c)	(i)	A species/molecule/ion with a space for/which can accept (a pair of)
electrons (to make a dative covalent bond)	1
Accept an electron deficient entity
Accept electron deficient ion
Reject just ‘a lover of negative charge’
Reject positive ion
Reject electron deficient element
 
(ii)	Brδ+ – Brδ– / Brδ+	1
Accept Br+
Be generous on symbols for delta
Reject Br2

(d)	(i)	Reaction 2	1
Reject two answers
 
(ii)	Oxidation number of carbon increases
or
oxygen is added (to the organic compound)	1
Reject loss of electrons alone / loss of electrons and addition of oxygen
 
(e)	(i)	Butane/CH3 CH2 CH2 CH3	1
Accept displayed formulae
Accept C2H5 instead of CH3 CH2
Reject C4H10
 
(ii)	Hydrogen (1)
Nickel (1)	2
Accept H2
Accept Ni
Accept platinum/Pt or palladium/Pd
Reject H
 
(iii)	Chlorine (1)
UV/ultraviolet/sunlight (1)	2
Accept Cl2
Accept visible light
Reject just ‘light’
[15]

26.	(a)	(i)	Any two of
•	(same) general formula
Accept (Same) general molecular formula
Reject (Same) molecular formula
•	(successive) members differ by CH2
•	(same) functional group/ (similar/same) chemical
properties/reactions
•	regular trend in physical properties
Reject same physical properties
Reject reference to a specific reaction e.g. same reaction with chlorine
	IGNORE “same properties”	2
 
(ii)	alkene(s)	1
Reject C=C
Reject alkane
 
(iii)	electrophilic addition (1) both needed
	IGNORE heterolytic and penalise homolytic
	hydrogen chloride/HCl (1)	2
Reject (Dilute) hydrochloric acid/dilute HCl /HCl(aq)
 
(b)	same molecular formula (1)
Accept same numbers of each atom
	different structural formulae/displayed formulae/
arrangement of atoms (1)	2
Accept different structure
Reject different arrangement in space

(c)	1-bromopropane faster (1)
Stand alone
Accept reverse statement
Any answer which gives 1-chloropropane as faster scores zero overall
	because C–Br bond weaker (than C–Cl) (1)
Accept reverse argument
Reject if no reference to carbon-halogen bond
	IGNORE attempted explanations of why C–Br bond weaker
	therefore lower activation energy/Eact (1)
[Lower Eact must be related to C–X bond]	3
Accept reverse argument
 
(d)

2 carbon chain with continuation bonds in repeat unit (1)
	All other atoms correct (1)
	IGNORE subscript n
	IGNORE where the bond to the CH3 goes e.g.
	 ½
	CH3 is fine	2
If more than one repeat unit given and number of repeat units stated or the repeat unit identified (2)
If repeat unit not stated or identified can score 2nd mark only
Reject 3 carbon chain
Or
Any repeat unit containing a double bond scores zero
 
(e)	Restricted rotation around double bond (1)
Accept no rotation/double bond cannot rotate (at room temperature)
	1-chloropropene has two different groups on both carbons/each
carbon (in the double bond)(but propene does not) (1)	2
Accept propene has two identical groups on one carbon (of the double bond) (but 1-chloropropene does not)
[14]

27.	(a)	H–C≡C–H
Bond angle: 180°
	Both needed with HCCH in a straight line	1
 
(b)	It also contains phosphine/PH3
hydrogen sulphide/H2S
ammonia/NH3
all 3 required	1
 
(c)	This method does not require crude oil (which may become too expensive)
Reject 1,2-dibromoethane is expensive [i.e. not an industrial method]
	Or
This method is more efficient (no tar deposition)
Accept second method is less efficient
Reject no heat required for cracking
	Or
Lime and coke are cheap/readily available	1
Reject calcium carbide is cheaper
 
(d)	Ethyne reacts only slowly
	Or
product still unsaturated/is an alkene/contains C=C/1,2-dibromoethene forms	1
Accept answers in terms of ethene e.g. ethene reacts more quickly etc
 
(e)	Any two from:
	Reaction with copper(I)
Reaction with silver ion
If neither of above given then “Acidity of ethyne” counts as one difference
	Decomposition under pressure
	Addition of water/reaction with dilute sulphuric acid to form ethanal	1
Reject reaction with halogen/hydrogen/polymeris ation (any reaction from second to last paragraph) but if given with two correct answers is neutral.
 
(f)	(i)	Ethene and bromine (water)	1
Accept ethene and bromine water formulae
Reject ethene liquid…

(ii)	Side arm flask/or equivalent with dropping funnel attached/stopper
and teat pipette
and heat indicated	1
Accept any workable set up
[7]

28.	(a)	A	1
 
(b)	B	1
[2]

29.	(a)	C	1
 
(b)	D	1
 
(c)	A	1
 
(d)	D	1
[4]

30.	(a)	A	1
 
(b)	C	1
[2]

31.	B
[1]

32.	C
[1]

33.	(a)	(i)
	3
Reject inaccurate placing of curly arrows
 
(ii)	The secondary carbocation/carbonium ion is more stable
than the primary (so forms when H+ adds)
OR
The secondary carbocation/carbonium ion is
stable because the methyl groups are electron donating	1
 
(iii)	2-bromopropane	1
 
(b)	Acidified potassium manganate(VII) / potassium
permanganate / KMnO4((aq))	1
 
(c)	

balanced and double bond broken (1)
CH3 on side chain (1)	2
Reject CH3 in unbranched chain
 
(d)	Poly(propene) is non-biodegradable / won’t break down in wet conditions (1)	1
 
(e)	(i)	propagation	1
 
(ii)	C6H14 / hexane /
Structural, displayed or skeletal formulae of hexane	1
[11]